Light-emitting apparatus including light-emitting diode

ABSTRACT

A light-emitting apparatus includes a first light emitter configured to emit visible light and including a plurality of light sources having color temperatures different from each other, a second light emitter configured to emit infrared rays, and a controller configured to adjust characteristics of the visible light and the infrared rays by controlling the first and second light emitters, in which each of the light sources includes a light-emitting diode chip and a wavelength conversion unit configured to convert a wavelength rage of light emitted from the light-emitting diode chip.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/203,607, filed on Nov. 29, 2018, which claims priority from and thebenefit of Korean Patent Application No. 10-2017-0163678, filed on Nov.30, 2017, each of which is hereby incorporated by reference for allpurposes as if fully set forth herein.

BACKGROUND Field

Exemplary embodiments of the invention relate to a light-emittingapparatus including light-emitting diodes.

Discussion of the Background

Most living things have adapted to act according to a change insunlight. The is human body also has adapted to the sunlight.Accordingly, the human biorhythm is changed according to a change in thesunlight. For example, in the morning, cortisol hormone is secreted dueto an influence of bright sunlight. The cortisol hormone helps supplyingblood to each organ of the body to cope with an external stimulus, suchas stress, so that a person can wake up from sleep and prepare anexternal activity. In the evening, melatonin hormone is secreted due toan influence of dark sunlight, which reduces blood pressure, therebyhelping a person to fall asleep.

In the modern society, there are many persons who spend more timeindoors than outdoors under the sunlight. An indoor lighting devicediffers greatly from the sunlight. For example, the indoor lightingdevice outputs white light, but does not have a spectrum distributed ina wide wavelength range like the sunlight. When the lighting device canoutput light having a spectrum similar to that of the sunlight, lightemitted from the lighting device would look natural and promote user'shealth.

The above information disclosed in this Background section is only forunderstanding of the background of the inventive concepts, and,therefore, it may contain information that does not constitute priorart.

SUMMARY

A light-emitting apparatus according to an exemplary embodiment canoutput light having a spectrum similar to that of external light.

Additional features of the inventive concepts will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the inventive concepts.

A light-emitting apparatus according to an exemplary embodiment includesa first light emitter configured to emit visible light and including aplurality of light sources having color temperatures different from eachother, a second light emitter configured to emit infrared rays, and acontroller configured to adjust characteristics of the visible light andthe infrared rays by controlling the first and second light emitters, inwhich each of the light sources includes a light-emitting diode chip anda wavelength conversion unit configured to convert a wavelength rage oflight emitted from the light-emitting diode chip.

The light-emitting apparatus may further include a user interfaceconnected to the controller, in which the controller is configured todisable the second light emitter when an input for prohibiting emissionof the infrared rays is received through the user interface.

The light-emitting apparatus may further include an optical sensorconfigured to sense external light, in which the controller is furtherconfigured to acquire a spectrum of the external light by communicatingwith the optical sensor, and control the first and second light emittersaccording to the spectrum of the external light.

The light-emitting apparatus may further include a storage medium, inwhich the controller is further configured to cause the storage mediumto store the spectrum of the external light during a first time.

The controller may be further configured to control the first and secondlight emitters according to the spectrum of the external light stored inthe storage medium during a second time.

The light-emitting apparatus may further include a user interfaceconnected to the controller, in which at least one of the first time andthe second time may be selected by a user through the user interface.

The light-emitting apparatus may further include a storage mediumconfigured to store a comparison spectrum, in which the controller isconfigured to acquire the comparison spectrum from the storage mediumand control the first and second light emitters according to thecomparison spectrum.

The light-emitting apparatus may further include a user interfaceconnected to the controller, in which the controller is configured tocontrol the first and second light emitters according to the comparisonspectrum acquired from the storage medium, at a time selected by a userthrough the user interface.

The light-emitting apparatus may further include control linesconnecting the first and second light emitters to the controller, inwhich the controller may include a driver configured to control thefirst and second light emitters by applying driving conditions to thecontrol lines.

The light-emitting apparatus may further include an optical sensorconfigured to sense light emitted from the first and second lightemitters, in which the controller is configured to compare a spectrum ofthe light emitted from the first and second light emitters with thespectrum of the external light, and to control the first and secondlight emitters according to a result of the comparison.

The second light emitter may include second light-emitting diodesconfigured to emit infrared rays having different wavelength ranges, thesecond light-emitting diodes may be connected to the controller throughsecond control lines, and the controller may be configured toindividually control the second light-emitting diodes through the secondcontrol lines.

The light-emitting apparatus may include an infrared sensor configuredto sense infrared rays of external light, in which the controller isconfigured to enable the first and second light emitters when anintensity of the sensed infrared rays of the external light is less thana predetermined level.

The light-emitting diode chip may be configured to emit light having awavelength of about 360 nm to about 420 nm.

The driver may be connected to the light sources through a part of thecontrol lines to control the light sources.

The controller may further include a processor configured to determinethe driving conditions.

A light-emitting apparatus according to an exemplary embodiment includesa controller, and light-emitting diodes configured to emit visible lightand infrared rays having wavelength ranges different from each other inresponse to a control of the controller, in which the controller isconfigured to adjust characteristics of the visible light and theinfrared rays by controlling the light-emitting diodes according to acomparison spectrum.

The light-emitting diodes may include first light-emitting diodesconfigured to emit the visible light, and second light-emitting diodesconfigured to emit the infrared rays.

The light-emitting apparatus may further include a user interfaceconnected to the controller, in which the controller is configured todisable the second light-emitting diodes when input for prohibitingemission of the infrared rays is received through the user interface.

The light-emitting apparatus may further include an optical sensorconfigured to sense external light, in which the controller isconfigured to acquire a spectrum of the external light by communicatingwith the optical sensor, and provides the spectrum of the external lightas the comparison spectrum.

The light-emitting apparatus may further include a storage medium, inwhich the controller is further configured to cause the storage mediumto store the spectrum of the external light during a first time, andcontrol the light-emitting diodes according to the spectrum of theexternal light stored in the storage medium during a second time.

The light-emitting apparatus may further include a storage mediumconfigured to store the comparison spectrum, in which the controller isconfigured to acquire the comparison spectrum from the storage medium.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate exemplary embodiments of theinvention, and together with the description serve to explain theinventive concepts.

FIG. 1 is a graph illustrating solar spectra measured at differenttimes.

FIG. 2 is a block diagram illustrating a light-emitting apparatusaccording to an exemplary embodiment.

FIG. 3 is a detailed block diagram illustrating a driver, a visiblelight emitter, and an infrared ray emitter of FIG. 2.

FIG. 4 and FIG. 5 are block diagrams illustrating the visible lightemitter of FIG. 3 according to exemplary embodiments.

FIG. 6 is a block diagram illustrating the visible light emitter of FIG.3 according to another exemplary embodiment.

FIG. 7 is a flowchart illustrating an operation method of alight-emitting apparatus according to an exemplary embodiment.

FIG. 8 is a flowchart illustrating the step S120 of FIG. 7 according toan exemplary embodiment.

FIG. 9 is a block diagram illustrating the infrared ray emitter of FIG.3 according to an exemplary embodiment.

FIG. 10 is a diagram illustrating wavelength ranges of light emittedfrom the light-emitting diodes of FIG. 9.

FIG. 11 is a block diagram illustrating a light-emitting apparatusaccording to an exemplary embodiment.

FIG. 12 is a flowchart illustrating an operation method of thelight-emitting apparatus according to an exemplary embodiment.

FIG. 13 is a block diagram illustrating a light-emitting apparatusaccording to an exemplary embodiment.

FIG. 14 is a block diagram illustrating a light-emitting apparatusaccording to another exemplary embodiment.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of various exemplary embodiments or implementations of theinvention. As used herein “embodiments” and “implementations” areinterchangeable words that are non-limiting examples of devices ormethods employing one or more of the inventive concepts disclosedherein. It is apparent, however, that various exemplary embodiments maybe practiced without these specific details or with one or moreequivalent arrangements. In other instances, well-known structures anddevices are shown in block diagram form in order to avoid unnecessarilyobscuring various exemplary embodiments. Further, various exemplaryembodiments may be different, but do not have to be exclusive. Forexample, specific shapes, configurations, and characteristics of anexemplary embodiment may be used or implemented in another exemplaryembodiment without departing from the inventive concepts.

Unless otherwise specified, the illustrated exemplary embodiments are tobe understood as providing exemplary features of varying detail of someways in which the inventive concepts may be implemented in practice.Therefore, unless otherwise specified, the features, components,modules, layers, films, panels, regions, and/or aspects, etc.(hereinafter individually or collectively referred to as “elements”), ofthe various embodiments may be otherwise combined, separated,interchanged, and/or rearranged without departing from the inventiveconcepts.

The use of cross-hatching and/or shading in the accompanying drawings isgenerally provided to clarify boundaries between adjacent elements. Assuch, neither the presence nor the absence of cross-hatching or shadingconveys or indicates any preference or requirement for particularmaterials, material properties, dimensions, proportions, commonalitiesbetween illustrated elements, and/or any other characteristic,attribute, property, etc., of the elements, unless specified. Further,in the accompanying drawings, the size and relative sizes of elementsmay be exaggerated for clarity and/or descriptive purposes. When anexemplary embodiment may be implemented differently, a specific processorder may be performed differently from the described order. Forexample, two consecutively described processes may be performedsubstantially at the same time or performed in an order opposite to thedescribed order. Also, like reference numerals denote like elements.

When an element, such as a layer, is referred to as being “on,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, connected to, or coupled to the other element or layer orintervening elements or layers may be present. When, however, an elementor layer is referred to as being “directly on,” “directly connected to,”or “directly coupled to” another element or layer, there are nointervening elements or layers present. To this end, the term“connected” may refer to physical, electrical, and/or fluid connection,with or without intervening elements. Further, the D1-axis, the D2-axis,and the D3-axis are not limited to three axes of a rectangularcoordinate system, such as the x, y, and z-axes, and may be interpretedin a broader sense. For example, the D1-axis, the D2-axis, and theD3-axis may be perpendicular to one another, or may represent differentdirections that are not perpendicular to one another. For the purposesof this disclosure, “at least one of X, Y, and Z” and “at least oneselected from the group consisting of X, Y, and Z” may be construed as Xonly, Y only, Z only, or any combination of two or more of X, Y, and Z,such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items.

Although the terms “first,” “second,” etc. may be used herein todescribe various types of elements, these elements should not be limitedby these terms. These terms are used to distinguish one element fromanother element. Thus, a first element discussed below could be termed asecond element without departing from the teachings of the disclosure.

Spatially relative terms, such as “beneath,” “below,” “under,” “lower,”“above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), andthe like, may be used herein for descriptive purposes, and, thereby, todescribe one elements relationship to another element(s) as illustratedin the drawings. Spatially relative terms are intended to encompassdifferent orientations of an apparatus in use, operation, and/ormanufacture in addition to the orientation depicted in the drawings. Forexample, if the apparatus in the drawings is turned over, elementsdescribed as “below” or “beneath” other elements or features would thenbe oriented “above” the other elements or features. Thus, the exemplaryterm “below” can encompass both an orientation of above and below.Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90degrees or at other orientations), and, as such, the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting. As used herein, thesingular forms, “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. Moreover,the terms “comprises,” “comprising,” “includes,” and/or “including,”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, elements, components, and/orgroups thereof, but do not preclude the presence or addition of one ormore other features, integers, steps, operations, elements, components,and/or groups thereof. It is also noted that, as used herein, the terms“substantially,” “about,” and other similar terms, are used as terms ofapproximation and not as terms of degree, and, as such, are utilized toaccount for inherent deviations in measured, calculated, and/or providedvalues that would be recognized by one of ordinary skill in the art.

As customary in the field, some exemplary embodiments are described andillustrated in the accompanying drawings in terms of functional blocks,units, and/or modules. Those skilled in the art will appreciate thatthese blocks, units, and/or modules are physically implemented byelectronic (or optical) circuits, such as logic circuits, discretecomponents, microprocessors, hard-wired circuits, memory elements,wiring connections, and the like, which may be formed usingsemiconductor-based fabrication techniques or other manufacturingtechnologies. In the case of the blocks, units, and/or modules beingimplemented by microprocessors or other similar hardware, they may beprogrammed and controlled using software (e.g., microcode) to performvarious functions discussed herein and may optionally be driven byfirmware and/or software. It is also contemplated that each block, unit,and/or module may be implemented by dedicated hardware, or as acombination of dedicated hardware to perform some functions and aprocessor (e.g., one or more programmed microprocessors and associatedcircuitry) to perform other functions. Also, each block, unit, and/ormodule of some exemplary embodiments may be physically separated intotwo or more interacting and discrete blocks, units, and/or moduleswithout departing from the scope of the inventive concepts. Further, theblocks, units, and/or modules of some exemplary embodiments may bephysically combined into more complex blocks, units, and/or moduleswithout departing from the scope of the inventive concepts.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure is a part. Terms,such as those defined in commonly used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of the relevant art and should not be interpreted in anidealized or overly formal sense, unless expressly so defined herein.

FIG. 1 is a graph illustrating solar spectra SPCTR1 and SPCTR2 measuredat different times of the day. In FIG. 1, a horizontal axis denotes awavelength and a vertical axis denotes energy.

Referring to FIG. 1, the solar spectra SPCTR1 and SPCTR2 are distributedover a wide wavelength range. Each of the solar spectra SPCTR1 andSPCTR2 is distributed over a wide wavelength range, which includes UVcorresponding to ultraviolet rays, VL corresponding to visible light,and IR corresponding to infrared rays.

The first solar spectrum SPCTR1 is measured at 12:00 o'clock and thesecond solar spectrum SPCTR2 is measured at 18:00 o'clock. The human eyerecognizes 12 o'clock sunlight more brightly than 18 o'clock sunlight.As well-known in the art, light recognized by the human eye is visiblelight. The first solar spectrum SPCTR1 has energy (or intensity) greaterthan that of the second solar spectrum SPCTR2 in the VL wavelength rangecorresponding to visible light.

Meanwhile, infrared rays included in the sunlight are not recognized bythe human eye, but may have a positive influence on the human bodyorgans. In addition, the infrared rays may be recognized by body organs,such as the skin of human. The infrared rays included in the sunlightalso have different levels of energy throughout the day. For example,the first solar spectrum SPCTR1 generally has energy greater than thatof the second solar spectrum SPCTR2 in the IR wavelength rangecorresponding to infrared rays.

As described above, the solar spectra are changed according to thepassage of time, and most living things have adapted to act according toa change in the sunlight. When an indoor lighting device may emit bothinfrared rays and visible light, and the emitted visible light andinfrared rays have characteristics similar to those of the sunlight thatchanges according to the passage of time, the lighting device canprovide effects similar to those provided by the sunlight includinglight of various wavelength ranges, and can be recognized by a person asif light similar to the sunlight is being provided.

FIG. 2 is a block diagram illustrating a light-emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 2, a light-emitting apparatus 100 may include acontroller 110, a visible light emitter 120, an infrared ray emitter130, at least one optical sensor 140, a storage medium 150, and a userinterface 160.

The controller 110 is connected to the visible light emitter 120, theinfrared ray emitter 130, the optical sensor 140, the storage medium150, and the user interface 160. The controller 110 may include aprocessor 111 and a driver 112.

The processor 111 may control the operations of the light-emittingapparatus 100. For example, the processor 111 may determine drivingconditions (or bias conditions) to be applied to the visible lightemitter 120 and the infrared ray emitter 130 on the basis of acomparison spectrum, and control the driver 112 to drive the visiblelight emitter 120 and the infrared ray emitter 130 under the determineddriving conditions. According to an exemplary embodiment, the processor111 may acquire a spectrum of external light (for example, sunlight) byusing the optical sensor 140, and uses the spectrum of the externallight as the comparison spectrum.

The driver 112 may drive the visible light emitter 120 and the infraredray emitter 130 under the driving conditions determined by the processor111. The driver 112 may drive the visible light emitter 120 and theinfrared ray emitter 130 according to various schemes. For example, thedriver 112 may adjust light to be emitted by adjusting levels ofcurrents which are applied to the visible light emitter 120 and theinfrared ray emitter 130. In this case, driving conditions determined bythe processor 111 may indicate the levels of the currents. In anotherexample, the driver 112 may adjust light to be emitted by adjustingwidths of voltage (or current) pulses which are applied to the visiblelight emitter 120 and the infrared ray emitter 130. In this case,driving conditions determined by the processor 111 may indicate thewidths of the pulses.

The visible light emitter 120 and the infrared ray emitter 130 may emitlight having spectrums that change according to the driving conditions.More particularly, a spectrum of visible light may be changed accordingto the driving conditions applied to the visible light emitter 120, anda spectrum of infrared rays may be changed according to the drivingconditions applied to the infrared ray emitter 130.

The visible light emitter 120 may include a plurality of light-emittingdiodes that emit visible light of various colors. The driver 112 mayindividually control the light-emitting diodes according to the drivingconditions determined by the processor 111. As such, the intensity ofthe visible light emitted from each of the light-emitting diodes may beadjusted. Accordingly, the spectrum of the visible light may be changedfrom mixed colors of light, which indicates that a color temperature isadjusted. For example, at around noon, visible light having a colortemperature of about 5,500 K may be emitted, and at around sunrise orsunset, visible light having a color temperature of about 4,500 K may beemitted.

The infrared ray emitter 130 may include at least one light-emittingdiode that emits infrared rays of a predetermined wavelength range. Thedriver 112 may drive the at least one infrared light-emitting diodeaccording to the driving conditions determined by the processor 111. Assuch, the intensity of the infrared rays emitted from the infrared rayemitter 130 may be adjusted, and thus, the spectrum of the infrared raysmay be changed.

The optical sensor 140 is connected to the processor 111. The opticalsensor 140 may sense external light in response to a request from theprocessor 111, and provide a sensing result to the processor 111. In anexemplary embodiment, the optical sensor 140 may include at least one ofvarious elements for sensing the external light, for example, chargecoupled device (CCD) and complementary metal-oxide semiconductor (CMOS)image sensors. In addition, the optical sensor 140 may include aninfrared sensor for sensing infrared rays of the external light. In thismanner, sensing sensitivity of the optical sensor 140 to the infraredrays may be improved.

In an exemplary embodiment, the optical sensor 140 may provide theprocessor 111 with source data for generating a spectrum of the externallight as a sensing result. In another exemplary embodiment, the opticalsensor 140 may generate a spectrum by sensing the external light, andtransmit the spectrum of the external light generated as the sensingresult to the processor 111.

The storage medium 150 is connected to the processor 111. The storagemedium 150 may store a data library for driving conditions. For example,when specific driving conditions are applied to the visible lightemitter 120 and the infrared ray emitter 130, the storage medium 150 maystore data for a spectrum of output light emitted by the visible lightemitter 120 and the infrared ray emitter 130. The spectrum data may bemeasured while applying driving conditions to the visible light emitter120 and the infrared ray emitter 130 after they are manufactured. Theprocessor 111 may select driving conditions with reference to the datalibrary stored in the storage medium 150 such that light emitted fromthe visible light emitter 120 and the infrared ray emitter 130 matchesthe spectrum of the external light.

In an exemplary embodiment, the storage medium 150 may include at leastone of various mediums accessible by the processor 111. For example, thestorage medium 150 may include at least one of storage mediums readableby a random access memory (RAM), a read only memory (ROM), and anothertype of processor 111.

The user interface 160 is connected to the processor 111. The userinterface 160 is configured to receive input of a user and transfer thereceived input to the processor 111. For example, a user may provide aninput through the user interface 160 to prohibit emission of infraredrays. In this case, the processor 111 may disable the infrared rayemitter 130 in response to the received input. The infrared ray emitter130 may be disabled according to various schemes. For example, thedriver 112 may include at least one switch capable of blocking drivingconditions applied to the infrared ray emitter 130, and may turn on oroff the switch under the control of the processor 111. As anotherexample, a user may provide an input through the user interface 160 toprohibit emission of visible light. When the input for prohibiting theemission of the visible light is received, the processor 111 may disablethe visible light emitter 120. For example, the driver 112 may includeat least one switch capable of blocking driving conditions applied tothe visible light emitter 120. In this manner, the light-emittingapparatus 100 may selectively emit visible light and infrared raysaccording to the selection of a user.

The user interface 160 may further include a module for displayingvarious types of information related to light emitted by thelight-emitting apparatus 100. For example, the processor 111 may causethe user interface 160 to display whether the light-emitting apparatus100 currently emits infrared rays and/or visible light and theintensities thereof. Furthermore, the processor 111 may cause the userinterface 160 to display a color temperature of light currently emittedfrom the light-emitting apparatus 100. In addition, the processor 111may cause the user interface 160 to display a spectrum of the lightcurrently emitted from the light-emitting apparatus 100.

According to an exemplary embodiment, the light-emitting apparatus 100includes the visible light emitter 120 that emits visible light and theinfrared ray emitter 130 that emits infrared rays. Furthermore, thelight-emitting apparatus 100 may adjust the emitted visible light andinfrared rays to have a spectrum similar to that of external light.Therefore, the light emitted from the light-emitting apparatus 100 mayhave a spectrum similar to that of sunlight in the IR wavelength rangecorresponding to the infrared rays as well as the VL wavelength rangecorresponding to the visible light. Accordingly, light emitted from thelight-emitting apparatus 100 may look natural and can provide effectssimilar to those provided by the sunlight.

FIG. 3 is a detailed block diagram illustrating the driver, the visiblelight emitter, and the infrared ray emitter of FIG. 2.

Referring to FIG. 3, the visible light emitter 120 includes first ton^(th) light-emitting diodes LED11 to LED1 n. The first to n^(th)light-emitting diodes LED11 to LED1 n are connected to the driver 112through visible light control lines VLCL.

The first to n^(th) light-emitting diodes LED11 to LED1 n may emitvisible light of different wavelength ranges, for example, light havingred, green, blue, amber, and cyan colors.

The visible light emitted from the first to n^(th) light-emitting diodesLED11 to LED1 n may be changed according to driving conditions appliedthrough the visible light control lines VLCL, for example, currentlevels or pulse widths. When the driving conditions applied to the firstto n^(th) light-emitting diodes LED11 to LED1 n are changed, theintensity of light of different wavelength ranges may be changed.Therefore, it is possible to change the spectrum of the visible lightemitted from the visible light emitter 120.

Each of the first to n^(th) light-emitting diodes LED11 to LED1 n mayinclude elements suitable for outputting light of a correspondingwavelength range. In an exemplary embodiment, each of the first ton^(th) light-emitting diodes LED11 to LED1 n may include alight-emitting diode chip for emitting light and a wavelength conversionunit for converting the wavelength range of light emitted therefrom. Forexample, each light-emitting diode may include an ultravioletlight-emitting diode chip and a wavelength conversion unit forconverting ultraviolet rays to light of a corresponding wavelengthrange. More particularly, the ultraviolet light-emitting diode chip mayemit light in a wavelength range of about 360 nm to about 420 nm,specifically, about 380 nm to about 420 nm, and more specifically, about400 nm to about 420 nm. In another example, each light-emitting diodemay include a blue light-emitting diode chip and a wavelength conversionunit for converting blue light to light of a corresponding wavelengthrange. In yet another example, each light-emitting diode may include alight-emitting diode chip for emitting light of a correspondingwavelength range without a wavelength conversion unit.

The infrared ray emitter 130 may include at least one infraredlight-emitting diode connected to at least one infrared control lineIRCL. When driving conditions applied to the at least one infraredlight-emitting diode are changed, the intensity of infrared rays may bechanged. Therefore, it is possible to change the spectrum of theinfrared rays emitted from the infrared ray emitter 130.

FIG. 4 and FIG. 5 are block diagrams illustrating a visible lightemitter according to exemplary embodiments.

Referring to FIG. 4, the visible light emitter 120′ according to anexemplary embodiment may include a red light-emitting diode RLED, agreen light-emitting diode GLED, a blue light-emitting diode BLED, whichare connected to the driver 112 through first, second, and third visiblelight control lines VLCL1 to VLCL3, respectively. For example, the redlight-emitting diode RLED may include a light-emitting diode chip foremitting ultraviolet rays and a red fluorescent substance for convertingemitted light to have a red wavelength, the green light-emitting diodeGLED may include a light-emitting diode chip for emitting ultravioletrays and a green fluorescent substance for converting emitted light tohave a green wavelength, and the blue light-emitting diode BLED mayinclude a light-emitting diode chip for emitting ultraviolet rays and ablue fluorescent substance for converting emitted light to have a bluewavelength. The intensity of light output from the light-emitting diodesRLED, GLED, and BLED may be adjusted according to driving conditionsrespectively applied thereto through the first to third visible lightcontrol lines VLCL1 to VLCL3. Therefore, color mixing of visible lightemitted from the light-emitting diodes RLED, GLED, and BLED may bechanged.

Referring to FIG. 5, the visible light emitter 120″ according to anexemplary embodiment may include a red green light-emitting diode RGLEDand a blue green light-emitting diode BGLED, which are connected to thedriver 112 through first and second visible light control lines VLCL1and VLCL2, respectively. The red green light-emitting diode RGLED emitsmixed red and green light, and the blue green light-emitting diode BGLEDemits mixed blue and green light. For example, the red greenlight-emitting diode RGLED may include a light-emitting diode chip foremitting ultraviolet rays, a red fluorescent substance for convertingemitted light to have a red wavelength, and a green fluorescentsubstance for converting the emitted light to have a green wavelength.The blue green light-emitting diode BGLED may include a light-emittingdiode chip for emitting ultraviolet rays, a blue fluorescent substancefor converting emitted light to have a blue wavelength, and a greenfluorescent substance for converting the emitted light to have a greenwavelength. The light-emitting diodes RGLED and BGLED may adjust theintensity of output light according to driving conditions respectivelyapplied thereto through the first and second visible light control linesVLCL1 and VLCL2.

FIG. 6 is a block diagram illustrating a visible light emitter accordingto another exemplary embodiment.

Referring to FIG. 6, the visible light emitter 120′″ according to anexemplary embodiment may include a warm white light-emitting diodemodule WWLED and a daylight color light-emitting diode module DLLED,which are connected to the driver 112 through first and second visiblelight control lines VLCL1 and VLCL2, respectively. The warm whitelight-emitting diode module WWLED may emit visible light having a colortemperature of about 4,000 K (Kelvin), and the daylight colorlight-emitting diode module DLLED may emit visible light having a colortemperature of about 6,500 K. In an exemplary embodiment, each of thewarm white light-emitting diode module WWLED and the daylight colorlight-emitting diode module DLLED may include a plurality oflight-emitting diodes, which may have the color temperatures accordingto color mixing of light emitted from the light-emitting diodes. Thelight-emitting diodes included in each light-emitting diode module maybe commonly controlled by a corresponding visible light control line.

In addition, the visible light emitter 120′″ may include combinations ofvarious light-emitting diode modules that emit white light. For example,a light-emitting diode module having a color temperature of about 1,800K and a light-emitting diode module having a color temperature of about4,000 K may be provided. In another example, a light-emitting diodemodule having a color temperature of about 1,800 K, a light-emittingdiode module having a color temperature of about 4,000 K, and alight-emitting diode module having a color temperature of about 6,500 Kmay be provided. In further another example, a light-emitting diodemodule having a color temperature of about 1,800 K, two light-emittingdiode modules having a color temperature of about 4,000 K, and alight-emitting diode module having a color temperature of about 6,500 Kmay be provided.

FIG. 7 is a flowchart illustrating an operation method of thelight-emitting apparatus according to an exemplary embodiment.

Referring to FIG. 2 and FIG. 7, at step S110, a spectrum is acquired bysensing external light. At step S120, a spectrum of output light isadjusted by controlling the visible light emitter 120 and the infraredray emitter 130 according to the acquired spectrum of the externallight. In this case, the output light includes visible light emittedfrom the visible light emitter 120 and infrared rays emitted from theinfrared ray emitter 130. As described above, the infrared rays as wellas the visible light may be adjusted according to the external light, sothat light having a spectrum similar to that of the external light maybe outputted.

FIG. 8 is a flowchart illustrating the step S120 of FIG. 7 according toan exemplary embodiment.

Referring to FIG. 2, FIG. 7, and FIG. 9, in some exemplary embodiments,the step S120 described above for adjusting the spectrum of output lightmay include additional steps to increase accuracy of the adjustment. Forexample, at step S210, a second spectrum may be acquired by sensing thelight emitted from the visible light emitter 120 and the infrared rayemitter 130. The at least one optical sensor 140 may sense the lightemitted from the visible light emitter 120 and the infrared ray emitter130, as well as the external light. In particular, the optical sensor140 may further sense mixed light outputted from the visible lightemitter 120 and the infrared ray emitter 130. In an exemplaryembodiment, an optical sensor for sensing the external light and anoptical sensor for sensing the output light may be respectively mountedat separate chips. In this case, when each optical sensor is directed toa proper direction, it is possible to efficiently sense desired light.

At step S220, the second spectrum of the emitted light is compared withthe spectrum of the external light. At step S230, the spectrums of thelight emitted from the visible light emitter 120 and the infrared rayemitter 130 are adjusted according to the comparison result. Theprocessor 111 may compare the second spectrum of the emitted light withthe spectrum data stored in the storage medium 150, and then correctdriving conditions applied to the visible light emitter 120 and theinfrared ray emitter 130 according to the comparison result, therebyoutputting light with a desired spectrum. In this case, the processor111 may update the corrected driving conditions in the storage medium150.

FIG. 9 is a block diagram illustrating an infrared ray emitter 130 ofFIG. 3 according to an exemplary embodiment.

Referring to FIG. 9, the infrared ray emitter 130 includes first tom^(th) light-emitting diodes LED21 to LED2 m. The first to m^(th)light-emitting diodes LED21 to LED2 m are connected to the driver 112through infrared control lines IRCL.

The first to m^(th) light-emitting diodes LED21 to LED2 m may emitinfrared rays of different wavelength ranges. The infrared rays emittedfrom the first to m^(th) light-emitting diodes LED21 to LED2 m may bechanged according to driving conditions applied through the infraredcontrol lines IRCL, for example, current levels or pulse widths. Whenthe driving conditions applied to the first to m^(th) light-emittingdiodes LED21 to LED2 m are changed, the intensity of the infrared rayshaving different wavelength ranges may be changed, and thus, thespectrum of the emitted infrared rays may be changed.

Referring back to FIG. 1, since the sunlight spectrum is alsodistributed in the IR wavelength range IR corresponding to the infraredrays, when infrared rays having a spectrum similar to that of thesunlight are emitted by adjusting the intensity of the infrared rays ofdifferent wavelength ranges in accordance to the spectrum of theexternal light as described above, light emitted from the light-emittingapparatus 100 may look natural and can provide effects similar to thoseprovided by the sunlight.

FIG. 10 is a diagram illustrating wavelength ranges of light emittedfrom the first to m^(th) light-emitting diodes LED21 to LED2 m.

A wavelength of infrared rays of the sunlight are distributed, and thus,may be divided into a plurality of wavelength ranges, as shown in FIG.10. The first to m^(th) light-emitting diodes LED21 to LED2 m may emitinfrared rays having wavelength ranges WVLRG1 to WVLRG3 selected fromthe divided wavelength ranges. FIG. 10 illustrates that the wavelengthof infrared rays of the sunlight is distributed from a first wavelengthWVL1 to an i^(th) wavelength WVLi. That is, the spectrum of the sunlightmay be distributed from the first wavelength WVL1 to the i^(th)wavelength WVLi. For example, the first wavelength WVL1 may be about 740nm and the i^(th) wavelength WVLi may be about 2,500 nm. In this case,the first to m^(th) light-emitting diodes LED21 to LED2 m may emitinfrared rays in the first wavelength range WVLRG1 between the firstwavelength WVL1 and the second wavelength WVL2, the second wavelengthrange WVLRG2 between the third wavelength WVL3 and the fourth wavelengthWVL4, and the third wavelength range WVLRG3 between the fifth wavelengthWVL5 and the sixth wavelength WVL6. In an exemplary embodiment, one ormore light-emitting diodes corresponding to each of the first to thirdwavelength ranges WVLRG1 to WVLRG3 may be provided. Furthermore, whenthe intensity of the infrared rays of each of the first to thirdwavelength ranges WVLRG1 to WVLRG3 is adjusted, the sum of the emittedinfrared rays may have a spectrum similar to the sunlight spectrumillustrated in FIG. 1.

It is well known in the art that near infrared rays provide variousbenefits, for example, support of a sterilizing action, activation ofcell growth, support of blood circulation, and the like. The wavelengthranges of the infrared rays emitted from the first to m^(th)light-emitting diodes LED21 to LED2 m may correspond to the nearinfrared rays. For example, the wavelength ranges of the infrared raysmay belong to about 740 nm to about 1,400 nm. However, the inventiveconcepts are not limited thereto. For example, the wavelength ranges ofthe infrared rays emitted from the first to m^(th) light-emitting diodesLED21 to LED2 m may be equal to or more than about 1,400 nm.

FIG. 11 is a block diagram illustrating a light-emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 11, a light-emitting apparatus 200 according to anexemplary embodiment may include a controller 210, a visible lightemitter 220, an infrared ray emitter 230, an optical sensor 240, firstand second storage mediums 251 and 252, and a user interface 260. Thecontroller 210 may include a processor 211 and a driver 212. The driver212, the visible light emitter 220, the infrared ray emitter 230, theoptical sensor 240, and the user interface 260 are substantially similarto the driver 112, the visible light emitter 120, the infrared rayemitter 130, the optical sensor 140, and the user interface 160described with reference to FIG. 2, and thus, repeated descriptionsthereof will be omitted to avoid redundancy.

According to the illustrated exemplary embodiment, the processor 211 mayacquire a spectrum of external light by using the optical sensor 240,and store the acquired spectrum of the external light in the secondstorage medium 252 as a comparison spectrum at a specific time.Alternatively, one or more proper optical spectrums may be stored inadvance in the second storage medium 252 as a comparison spectrumwithout the sensing step in the optical sensor 240. In this case, theoptical sensor 240 may be omitted.

Then, the comparison spectrum stored in the second storage medium 252may be used at a different time. At the different time, the processor211 may read the stored comparison spectrum, determine drivingconditions on the basis of the comparison spectrum, and control thedriver 212 to drive the visible light emitter 220 and the infrared rayemitter 230 under the determined driving conditions.

In an exemplary embodiment, the processor 211 may acquire a spectrum bysensing light emitted from the visible light emitter 220 and theinfrared ray emitter 230 by using the optical sensor 240, compare thespectrum of the emitted light with the stored comparison spectrum, andcorrect the driving conditions according to the comparison result.

The user interface 260 may receive input regarding a selection of timefor sensing the spectrum of the external light. The processor 211 mayacquire the spectrum of the external light by using the optical sensor240 at the selected time and store the acquired spectrum of the externallight in the second storage medium 252 as a comparison spectrum.

The user interface 260 may receive input regarding a selection of anemission time according to the comparison spectrum. At the selectedtime, the processor 211 may determine driving conditions according tothe comparison spectrum, and control the driver 212 to drive the visiblelight emitter 220 and the infrared ray emitter 230 under the determineddriving conditions. In this manner, the light-emitting apparatus 200 mayemit light, which has a spectrum similar to the comparison spectrum,such as the spectrum of sunlight acquired at a time desired by a user ora proper optical spectrum stored in advance, at a different time. Forexample, when a user selects multiple times for sensing the spectrum ofthe external light, and selects multiple times for outputting lightaccording to the selected external light, the light-emitting apparatus200 may provide light at the times selected by the user, which issimilar to sunlight, at different times. In another example, when a userselects optical spectrums stored in advance and selects multiple timesfor outputting light according to the selected times, the light-emittingapparatus 200 may provide light according to the optical spectrumsselected at the times desired by the user.

The first storage medium 251 may be substantially similar to the storagemedium 150 of FIG. 2. When specific driving conditions are applied tothe visible light emitter 220 and the infrared ray emitter 230, thefirst storage medium 251 may store data for a spectrum of output lightemitted by the visible light emitter 220 and the infrared ray emitter230. The data stored in the first storage medium 251 may be referred towhen the processor 211 determines driving conditions. The second storagemedium 252 may store the comparison spectrum as described above. Thefirst storage medium 251 and the second storage medium 252 may beincluded in one storage medium in which storage areas are logicallydivided. Alternatively, the first storage medium 251 and the secondstorage medium 252 may be provided as physically divided storage areas.

FIG. 12 is a flowchart illustrating an operation method of thelight-emitting apparatus according to an exemplary embodiment.

Referring to FIG. 11 and FIG. 12, at step S310, a spectrum is acquiredby sensing external light at a first time. At step S320, the acquiredspectrum of the external light is stored in the second storage medium252. At step S330, a spectrum of output light is adjusted by controllingthe visible light emitter 120 and the infrared ray emitter 130 accordingto the stored spectrum of the external light at a subsequent secondtime. In this manner, the light-emitting apparatus 200 can emit lightaccording to the spectrum of the external light at a different time.

FIG. 13 is a block diagram illustrating a light-emitting apparatusaccording to an exemplary embodiment.

Referring to FIG. 13, a light-emitting apparatus 300 may include acontroller 310, a visible light emitter 320, an infrared ray emitter330, an optical sensor 340, first and second storage mediums 351 and352, a user interface 360, and an infrared sensor 370. The controller310 may include a processor 311 and a driver 312.

The controller 310, the visible light emitter 320, the infrared rayemitter 330, the optical sensor 340, the first and second storagemediums 351 and 352, and the user interface 360 may be substantiallysimilar to the controller 210, the visible light emitter 220, theinfrared ray emitter 230, the optical sensor 240, the first and secondstorage mediums 251 and 252, and the user interface 260 of FIG. 11. Assuch, repeated descriptions thereof will be omitted to avoid redundancy.

The infrared sensor 370 according to an exemplary embodiment isconnected to the controller 310. The infrared sensor 370 is configuredto sense infrared rays of external light. For example, the infraredsensor 370 may be enabled when other elements of the light-emittingapparatus 300 are in a sleep mode, and may sense the infrared rays ofthe external light. For example, the infrared sensor 370 may sense awavelength range of about 740 nm to about 1,500 nm, specifically, about800 nm to about 1,000 nm, more specifically, about 850 nm to about 950nm.

The processor 311 may enable the visible light emitter 320 and theinfrared ray emitter 330 when the intensity of the sensed infrared raysis less than a critical level. In addition, the processor 311 maydisable the visible light emitter 320 and the infrared ray emitter 330when the intensity (or the energy level) of the sensed infrared rays isequal to or greater than the critical level. For example, the driver 312may include switches capable of blocking or permitting drivingconditions applied to the visible light emitter 320 and the infrared rayemitter 330, and turn on or off the switches under the control of theprocessor 311. According to the illustrated exemplary embodiment, whenthe intensity of the external light is relatively low, thelight-emitting apparatus 300 may emit light without a command of a userfor the user's convenience.

In an exemplary embodiment, the infrared sensor 370 may be omitted andits function may be performed by the optical sensor 340.

FIG. 14 is a block diagram illustrating a light-emitting apparatusaccording to another exemplary embodiment.

Referring to FIG. 14, a light-emitting apparatus 400 according to anexemplary embodiment may include a controller 410, a visible lightemitter 420, an infrared ray emitter 430, an optical sensor 440, firstand second storage mediums 451 and 452, a user interface 460, and amotion sensor 470.

The controller 410, the visible light emitter 420, the infrared rayemitter 430, the optical sensor 440, the first and second storagemediums 451 and 452, and the user interface 460 may be substantiallysimilar to the controller 210, the visible light emitter 220, theinfrared ray emitter 230, the optical sensor 240, the first and secondstorage mediums 251 and 252, and the user interface 260 of FIG. 11. Assuch, repeated descriptions thereof will be omitted to avoid redundancy.

The motion sensor 470 is connected to the controller 410. The motionsensor 470 may be configured to detect a motion of an external object.The motion sensor 470 may include any one of various types of motionsensors. For example, the motion sensor 470 may output light orelectromagnetic waves, for example, infrared rays, and detect theinterruption or reflection of the outputted light or electromagneticwaves, thereby detecting the motion of the external object.

A processor 411 may enable the visible light emitter 420 and theinfrared ray emitter 430 when the motion is detected. In addition, whenno motion is detected, after a predetermines time passes therefrom, theprocessor 411 may disable the visible light emitter 420 and the infraredray emitter 430. According to the illustrated exemplary embodiment, thelight-emitting apparatus 400 may emit light when a user is locatedaround the light-emitting apparatus 400 without input of a command fromthe user, which may provide user convenience.

According to the exemplary embodiments, a light-emitting apparatus mayoutput light having a spectrum substantially similar to that of externallight.

Although certain exemplary embodiments and implementations have beendescribed herein, other embodiments and modifications will be apparentfrom this description. Accordingly, the inventive concepts are notlimited to such embodiments, but rather to the broader scope of theappended claims and various obvious modifications and equivalentarrangements as would be apparent to a person of ordinary skill in theart.

What is claimed is:
 1. A light-emitting apparatus comprising: a firstlight emitter configured to emit visible light, the first light emittercomprising a plurality of light sources having color temperaturesdifferent from each other; a second light emitter configured to emitinfrared rays; and a controller configured to adjust characteristics ofthe visible light and the infrared rays by controlling the first andsecond light emitters, wherein each of the light sources comprises alight-emitting diode chip and a wavelength conversion unit configured toconvert a wavelength rage of light emitted from the light-emitting diodechip.